Display screen or portion thereof with a graphical user interface



FIG. 1 is a front view for a display screen with a graphic userinterface showing my new design;

FIG. 2 is a front view of a second embodiment thereof;

FIG. 3 is a front view of a third embodiment thereof;

FIG. 4 is a front view of a fourth embodiment thereof;

FIG. 5 is a front view of a fifth embodiment thereof; and,

FIG. 6 is a front view of a sixth embodiment thereof.

The outermost broken lines represent the display screen or portionthereof and form no part of the claimed design. The broken lines withinthe display screen represent text and graphical elements that form nopart of the claimed design.

CLAIM The ornamental design for a display screen or portion thereof witha graphical user interface, as shown and described.